1. Field of the Invention
The present invention is directed to a non-rotating, telescoping pole which may be extended to elevate a birdhouse, flag or the like, and which may be telescoped into a shorter, compact, easy-to-handle structure for carrying, storage and shipping.
2. Brief Description of the Prior Art
Telescoping poles have been developed for mounting a birdhouse, flag or the like. One advantage of such a structure is that the unit can be constructed on the site from relatively short sections which are easier to carry, store and ship than a traditional rigid, one-piece pole.
Telescoping poles usually have two or more concentrically disposed tubular sections that are axially movable with respect to each other. Relative movement of the sections is inhibited with a locking device housed within one or more of the inner sections. The locking device typically comprises a pin that is biased to extend from an inner section through a hole in an adjacent outer section.
The tubular sections usually rotate with respect to each other so that there must be a stop means to keep the inner section from being pulled out of the outer section, which will happen, unless by chance the pin is in alignment with the hole as the inner section is extended. A common stop means comprises a bushing ring within the upper end of the intermediate and bottom sections for coaction with a detent ring which is provided at the lower end of the top and intermediate sections. As the sections are extended axially, the detent ring at the bottom of each inner section contacts the annular ring at the top of the adjacent outer section to limit the upward extension of the tubes. Each of the inner tubes is then rotated in the respective outer tube until the pin snaps into the hole in the outer tube. The bushing rings, in addition to serving as a stop, maintain a space between the sections to reduce friction between sections as they slide within each other. This is important as it is desirable to avoid the use of ropes and pulleys to raise and lower the sections weighted with a birdhouse, flag or the like. Such prior art telescoping poles, even those without pulleys, require the manufacture of additional parts (e.g., bushing and detent) and additional installation steps that increase the cost of assembly. Furthermore, the need for internal parts increases the likelihood of adjacent ill-fitting sections and also increases maintenance requirements.
Since the tubular sections of a conventional telescoping pole rotate inside each other, the orientation of a birdhouse, flag or the like mounted on the pole will not necessarily be the same when the item is put up and taken down. When the birdhouse is for a purple martin colony, this is of critical importance since martins recognize their own nest compartment in a purple martin birdhouse by its height, relative position and compass direction. If a birdhouse is repositioned in a different compass direction, havoc will break out. Purple martins will go into the compartment in the position where their nest was and perhaps find nestlings, when all they had was eggs. In such case, they may throw the foreign young out. Others, while looking for their nests may trespass into the compartments of others, which can result in prolonged and potentially lethal battles. The end result of which may be reproductive failure, leading to colony-site abandonment.
With some prior art telescoping poles, a person can mark the sections to ensure that the birdhouse is repositioned with the correct polarization, but people either forget to mark the sections or forget, between uses, what the markings mean. There are also non-rotating telescoping poles with elaborate and complicated mechanisms to prevent rotation of the sections or the house. Such means usually include elongated guides which are formed separately and attached to the telescoping members, increasing manufacturing and maintenance costs as described above.
In view of the above, it is an object of the present invention to provide a non-rotating telescoping pole formed of two or more sections without additional parts such as bushings, detents and pulleys. It is another object to provide a non-rotating telescoping pole that ensures consistent polarization of a birdhouse, such as a purple martin birdhouse, when it is taken down and reinstalled on a pole. Other objects and features of the invention will be in part apparent and in part pointed out hereinafter.
In accordance with the invention, a non-rotatable telescoping pole for mounting a birdhouse, flag or the like with consistent polarization has an inner tubular section with first and second ends and a cross-section having the shape of a convex polygon, such as an equilateral triangle. An outer tubular section, with first and second ends, has a bore generally corresponding to the cross-section of the inner section, the bore of the outer section being in frictional contact with the inner tubular section and the inner tubular section axially slidable within the bore of the outer section.
The outer tubular section also has a hole proximate its second end and the inner tubular section has a hole proximate its first end. The inner tubular section has a pin aligned with said hole and a biasing element that biases the pin outwardly through the hole. The pin at the first end of the inner section is also aligned with the hole in the outer section when the inner section is extended. The pin is biased outwardly through the hole in the outer section, thus impeding further relative axial movement of the inner and outer sections. Relative rotation of the inner and outer sections is prevented by engagement of the inner tubular section with the bore of the outer section.
The invention summarized above comprises the constructions hereinafter described, the scope of the invention being indicated by the subjoined claims.